Energy Food Review - No 234 - October 2004

Back in the days when I didn’t own a car or even a mattress, my hierarchy of financial priorities was simple: Climbing trips held top honors and food suffered alone in last place. A typical day’s rations usually consisted of rice, beans, and “power muffins” — durable, tasteless, five-cent gems made from a paper-pulp-like batter of oatmeal, eggs, and water.
My culinary world changed when a generous friend, seeing me lagging during the hike into a backcountry rock route, passed me a silver-wrapped snack. A few bites of the tasty bar was all it took for me to realize the benefits of its dense caloric value and convenience. I’ve been a fan of energy foods ever since, and after eating hundreds — if not thousands — of these sweet goodies over the last 10 years, it was about time to put my experience to good use.
For this review, we chose six of the leading energy bars and five popular gels. Twelve of us munched our hearts out while bouldering, hiking, cragging, and alpine climbing. We tested for taste, texture, ease of digestion, and overall performance, and found — due to the individual requirements of each tester — that many products had both ardent fans and opponents.
We also took into consideration a product’s ability to stand up to the rigors of living in a climbing pack for a day (or two or three), and to extreme temperatures. We even scrutinized packaging, as nobody wants to carry a machete for hacking open snacks.
During our testing we tried to use the products as the manufacturers intended. Gels were gulped for quick energy blasts before boulder problems, redpoint projects, or crux pitches, or consumed regularly on long steady days. Bars were chewed for endurance outings like multi-pitch climbing, alpine climbing, or as a meal replacement for a long day at the crags.
“For the athlete or weekend warrior, energy foods are utilized as instant energy and can extend endurance,” says Pam Vagnieres, MS, CSCS of Boulder’s Nutri-Physique, and our expert nutrition resource for this review. “For the sedentary, they are primarily sugar and carbohydrate, and when these macronutrients are not used immediately, insulin will shuttle them into fat cells. These products are intended for athletes and people who exercise rigorously, not for yuppies sitting at their computers all day.”

Which carbs? Understanding the basic ingredients of the bars and gels in this review and how best to use them for a given activity is the first step in making an educated choice about which fuel is right for you. And although carbohydrates are the dominant component in most sports food, the type of carb and what it is combined with can drastically alter its effect.
Fructose and glucose are simple sugars (monosaccharides), and are relatively easy to digest, and provide a good source of quick energy. Honey is mainly a combination of fructose (38 percent), glucose (31 percent), and water. It is an easily digested source of natural sugar and provides even, long-burning energy. Honey also contains naturally occurring vitamins, minerals, and antioxidants, and is less likely to cause a blood-sugar spike when compared to maltodextrin or glucose.
Maltodextrin is formed from linking glucose molecules together into short chains, making it a complex sugar or polysaccharide. Most people find this manufactured glucose polymer is very easy to digest and provides an excellent source of quick energy. Brown rice syrup is also made up of short chains of monosaccharides, but it’s less processed than maltodextrin.

You need more than carbs. Protein, fat, and fiber are all important ingredients to consider when shopping for endurance food. Their complex molecules require a longer digestion and absorption process than that of carbohydrates, causing the absorption of any carbs eaten in conjunction to be slowed as well. When these ingredients are combined into a bar, the net result is a slow-burning fuel that provides a long and even energy release.
Not many people realize that protein supplies up to 10 percent of the energy used during sustained efforts lasting more than 90 minutes. If you don’t supply your body with a protein source during such periods, your muscles will be cannibalized for use as fuel in a process called gluconeogenesis. Consuming small amounts of protein along with carbohydrates slows this process and increases endurance. Most of the bars we tested contain soy or whey protein to address this nutritional requirement. Nuts are another good source of protein.
In addition to protein, many bars and gels contain amino acids. Amino acids are the specific chemicals that make up protein and often are referred to as protein’s “building blocks.” Some 20 amino acids make up living muscle tissue; some of those can be used for energy, while others can’t. By hand picking the specific energizing amino acids, manufacturers hope to better guard against gluconeogenesis.
Fat from nut or seed sources is present in many of the bars. A few bars contain dairy fat, and those who have trouble digesting dairy should decide if the quantities found in the bars might bother them. Like protein, fat helps to even out the quick carbohydrate burn and provides a long-lasting energy source.
Fiber, although indigestible and calorie-void, is another important link in the absorption equation — it slows the rate in which carbs enter the bloodstream. It also makes products a little more like a whole, natural food. Fiber in these bars comes from soy, nut, grain, and fruit sources. Some of the fiber is a naturally occurring result of an ingredient choice, while a few companies specifically add fiber. Again, look for some fiber in bars for extended burn times.

All kinds of spikes. With all this talk of energy sources, it is hard not to mention the glycemic index (GI), a rating system that calibrates a food’s effect on blood-sugar levels. Higher ranked foods raise blood sugar levels more than lower ranking foods. Gels have high GI ratings due to their easily absorbed simple and complex carbs. Bars, with the addition of the more slowly digested protein and fat, and non-digestable fiber, have a much lower GI.
Diving into the specific GI of our test products’ carbohydrate sources reveals that maltodextrin has a GI rating of 105, honey, 55, glucose, 50, and fructose, 22. This means that maltodextrin provides the fastest blood sugar level increase and fructose the slowest. For comparison, a baked potato’s GI is 85, with bananas ranking at 53, and apples 38.
Caffeine is present in some of the products tested and many people appreciate its pick-me-up effect. Caffeine does improve endurance, as it helps the body mobilize fatty acids for use as energy, sparing the body’s glycogen (stored sugar) reserves. These effects can be stronger for those who don’t consume caffeine on a regular basis. And even though most of the products reviewed have much lower levels of caffeine than the 200 to 300mg found in an eight-ounce cup of joe, it’s good to remember that ingesting caffeine during exercise can cause stomach distress, the jitters, and impaired performance.

Vitamins and minerals. All of the gels and bars tested contain different amounts of vitamins and minerals. These essential nutrients give the body supplies for replacing what it uses during exercise. Look for vitamins C, E, any of the eight Bs, and the minerals calcium, magnesium, potassium, and sodium. Vitamins C and E are highly beneficial for their abilities to quench free radicals, unstable molecules produced by oxidation in the body that damage healthy cells. As one’s exercise levels increases, so does free-radical production.

When and how? Okay, you’re ready to try out a few high-tech snacks, but when is the best time to ingest them? For short efforts like bouldering or flashing a crux pitch, try swallowing a gel and a few mouthfuls of water about 20 to 30 minutes before your attempt. This will give you the best chance of timing your increased blood sugar levels with the demands of the project. For endurance days, gels can be consumed at a rate of about one every 45 minutes with eight ounces of water. Bars have a slower absorption rate and are best snacked on throughout the day to ensure consistent and even energy levels. It’s a good idea to start munching before you feel hungry, maybe a few hours after breakfast. Eating half a bar every 45 minutes, or a full bar every hour and a half, is a good starting point for experimenting. Drink adequate water (eight to 10 ounces per serving) when eating bars or any other solid food during exercise to ensure proper digestion.
Another great way to help keep glycogen levels topped off and your energy level high is to consume a sports drink during exercise instead of water. If you mix the drink too strong, however, your body’s ability to hydrate will actually slow from the over-abundance of carbs. Make sure to follow the manufacturer’s mixing directions and don’t put too much powder in your bottle.
Those blessed with an iron gut can fire down just about anything short of week-old road kill and feel great, while more sensitive types may spend quite some time nailing down what powers them best. When in doubt, try out your energy system before the big day. It’s no fun to run out of juice by underestimating your caloric requirements, or worse yet, not being able to eat your snacks because of the knots they throw into your belly.